/*
 * 3d标签云
 * 功能：鼠标移入标签，当前标签静止放大
 * 说明：
 * */
/*
 * 给原生 HTML 实现用的tagcloud.js源码
 * window.tagcloud = (function(win, doc)
 */

/*
 * vue实现
 * export const tagcloud = (function (win = window, doc = document)
 */

window.tagcloud = (function (win, doc) {
  // ns
  // 判断对象
  function isObject(obj) {
    return Object.prototype.toString.call(obj) === '[object Object]'
  }

  // 构造函数
  function TagCloud(options) {
    var self = this

    self.config = TagCloud._getConfig(options)
    self.box = self.config.element //组件元素
    self.fontsize = self.config.fontsize //平均字体大小
    self.radius = self.config.radius //滚动半径
    self.depth = 2 * self.radius //滚动深度
    self.size = 2 * self.radius //随鼠标滚动变速作用区域

    self.mspeed = TagCloud._getMsSpeed(self.config.mspeed)
    self.ispeed = TagCloud._getIsSpeed(self.config.ispeed)
    self.items = self._getItems()

    self.direction = self.config.direction //初始滚动方向
    self.keep = self.config.keep //鼠标移出后是否保持之前滚动

    //初始化
    self.active = false //是否为激活状态
    self.lasta = 1
    self.lastb = 1
    self.mouseX0 = self.ispeed * Math.sin((self.direction * Math.PI) / 180) //鼠标与滚动圆心x轴初始距离
    self.mouseY0 = -self.ispeed * Math.cos((self.direction * Math.PI) / 180) //鼠标与滚动圆心y轴初始距离
    self.mouseX = self.mouseX0 //鼠标与滚动圆心x轴距离
    self.mouseY = self.mouseY0 //鼠标与滚动圆心y轴距离
    self.index = -1

    //鼠标移入
    TagCloud._on(self.box, 'mouseover', function () {
      self.active = true
    })
    //鼠标移出
    TagCloud._on(self.box, 'mouseout', function () {
      self.active = false
    })

    //鼠标在内移动
    TagCloud._on(self.keep ? win : self.box, 'mousemove', function (ev) {
      var oEvent = win.event || ev
      var boxPosition = self.box.getBoundingClientRect()
      self.mouseX =
        (oEvent.clientX - (boxPosition.left + self.box.offsetWidth / 2)) / 5
      self.mouseY =
        (oEvent.clientY - (boxPosition.top + self.box.offsetHeight / 2)) / 5
    })

    for (var j = 0, len = self.items.length; j < len; j++) {
      self.items[j].element.index = j

      //鼠标移出子元素,当前元素静止放大
      self.items[j].element.onmouseover = function () {
        self.index = this.index
      }

      //鼠标移出子元素,当前元素继续滚动
      self.items[j].element.onmouseout = function () {
        self.index = -1
      }
    }

    //定时更新
    TagCloud.boxs.push(self.box)
    self.update(self) //初始更新
    self.box.style.visibility = 'visible'
    self.box.style.position = 'relative'
    self.box.style.minHeight = 1.2 * self.size + 'px'
    self.box.style.minWidth = 2.5 * self.size + 'px'
    for (var j = 0, len = self.items.length; j < len; j++) {
      self.items[j].element.style.position = 'absolute'
      self.items[j].element.style.zIndex = j + 1
    }
    self.up = setInterval(function () {
      self.update(self)
    }, 30)
  }

  //实例
  TagCloud.boxs = [] //实例元素数组
  // 静态方法们
  TagCloud._set = function (element) {
    if (TagCloud.boxs.indexOf(element) == -1) {
      //ie8不支持数组的indexOf方法
      return true
    }
  }

  //添加数组IndexOf方法
  if (!Array.prototype.indexOf) {
    Array.prototype.indexOf = function (elt /*, from*/) {
      var len = this.length >>> 0
      var from = Number(arguments[1]) || 0
      from = from < 0 ? Math.ceil(from) : Math.floor(from)
      if (from < 0) from += len

      for (; from < len; from++) {
        if (from in this && this[from] === elt) return from
      }
      return -1
    }
  }

  TagCloud._getConfig = function (config) {
    var defaultConfig = {
      //默认值
      fontsize: 16, //基本字体大小, 单位px
      radius: 60, //滚动半径, 单位px
      mspeed: 'normal', //滚动最大速度, 取值: slow, normal(默认), fast
      ispeed: 'normal', //滚动初速度, 取值: slow, normal(默认), fast
      direction: 135, //初始滚动方向, 取值角度(顺时针360): 0对应top, 90对应left, 135对应right-bottom(默认)...
      keep: true //鼠标移出组件后是否继续随鼠标滚动, 取值: false, true(默认) 对应 减速至初速度滚动, 随鼠标滚动
    }

    if (isObject(config)) {
      for (var i in config) {
        if (config.hasOwnProperty(i)) {
          //hasOwnProperty()用来判断一个属性是定义在对象本身而不是继承自原型链
          defaultConfig[i] = config[i] //用户配置
        }
      }
    }

    return defaultConfig // 配置 Merge
  }
  TagCloud._getMsSpeed = function (mspeed) {
    //滚动最大速度
    var speedMap = {
      slow: 1.5,
      normal: 3,
      fast: 5
    }
    return speedMap[mspeed] || 3
  }
  TagCloud._getIsSpeed = function (ispeed) {
    //滚动初速度
    var speedMap = {
      slow: 10,
      normal: 25,
      fast: 50
    }
    return speedMap[ispeed] || 25
  }
  TagCloud._getSc = function (a, b) {
    var l = Math.PI / 180
    //数组顺序0,1,2,3表示asin,acos,bsin,bcos
    return [Math.sin(a * l), Math.cos(a * l), Math.sin(b * l), Math.cos(b * l)]
  }

  TagCloud._on = function (ele, eve, handler, cap) {
    if (ele.addEventListener) {
      ele.addEventListener(eve, handler, cap)
    } else if (ele.attachEvent) {
      ele.attachEvent('on' + eve, handler)
    } else {
      ele['on' + eve] = handler
    }
  }

  // 原型方法
  TagCloud.prototype = {
    constructor: TagCloud, // 反向引用构造器

    update: function () {
      var self = this,
        a,
        b

      if (!self.active && !self.keep) {
        self.mouseX =
          Math.abs(self.mouseX - self.mouseX0) < 1
            ? self.mouseX0
            : (self.mouseX + self.mouseX0) / 2 //重置鼠标与滚动圆心x轴距离
        self.mouseY =
          Math.abs(self.mouseY - self.mouseY0) < 1
            ? self.mouseY0
            : (self.mouseY + self.mouseY0) / 2 //重置鼠标与滚动圆心y轴距离
      }

      a =
        -(
          Math.min(Math.max(-self.mouseY, -self.size), self.size) / self.radius
        ) * self.mspeed
      b =
        (Math.min(Math.max(-self.mouseX, -self.size), self.size) /
          self.radius) *
        self.mspeed

      if (Math.abs(a) <= 0.01 && Math.abs(b) <= 0.01) {
        return
      }

      self.lasta = a
      self.lastb = b

      var sc = TagCloud._getSc(a, b)

      for (var j = 0, len = self.items.length; j < len; j++) {
        var rx1 = self.items[j].x,
          ry1 = self.items[j].y * sc[1] + self.items[j].z * -sc[0],
          rz1 = self.items[j].y * sc[0] + self.items[j].z * sc[1]

        var rx2 = rx1 * sc[3] + rz1 * sc[2],
          ry2 = ry1,
          rz2 = rz1 * sc[3] - rx1 * sc[2]

        if (self.index == j) {
          self.items[j].scale = 1 //取值范围0.6 ~ 3
          self.items[j].fontsize = 16
          self.items[j].alpha = 1
          self.items[j].element.style.zIndex = 99
        } else {
          var per = self.depth / (self.depth + rz2)
          self.items[j].x = rx2
          self.items[j].y = ry2
          self.items[j].z = rz2

          self.items[j].scale = per //取值范围0.6 ~ 3
          self.items[j].fontsize = Math.ceil(per * 2) + self.fontsize - 6
          self.items[j].alpha = 1.5 * per - 0.5
          self.items[j].element.style.zIndex = Math.ceil(per * 10 - 5)
        }
        self.items[j].element.style.fontSize = self.items[j].fontsize + 'px'
        self.items[j].element.style.left =
          self.items[j].x +
          (self.box.offsetWidth - self.items[j].offsetWidth) / 2 +
          'px'
        self.items[j].element.style.top =
          self.items[j].y +
          (self.box.offsetHeight - self.items[j].offsetHeight) / 2 +
          'px'
        self.items[j].element.style.filter =
          'alpha(opacity=' + 100 * self.items[j].alpha + ')'
        self.items[j].element.style.opacity = self.items[j].alpha
      }
    },

    _getItems: function () {
      var self = this,
        items = [],
        element = self.box.children, // children 全部是Element
        length = element.length,
        item

      for (var i = 0; i < length; i++) {
        item = {}
        item.angle = {}
        item.angle.phi = Math.acos(-1 + (2 * i + 1) / length)
        item.angle.theta = Math.sqrt((length + 1) * Math.PI) * item.angle.phi
        item.element = element[i]
        item.offsetWidth = item.element.offsetWidth
        item.offsetHeight = item.element.offsetHeight
        item.x =
          self.radius *
          1.5 *
          Math.cos(item.angle.theta) *
          Math.sin(item.angle.phi)
        item.y =
          self.radius *
          1.5 *
          Math.sin(item.angle.theta) *
          Math.sin(item.angle.phi)
        item.z = self.radius * 1.5 * Math.cos(item.angle.phi)
        item.element.style.left =
          item.x + (self.box.offsetWidth - item.offsetWidth) / 2 + 'px'
        item.element.style.top =
          item.y + (self.box.offsetHeight - item.offsetHeight) / 2 + 'px'
        items.push(item)
      }

      return items //单元素数组
    }
  }

  if (!doc.querySelectorAll) {
    //ie7不支持querySelectorAll，所以要重新定义
    doc.querySelectorAll = function (selectors) {
      var style = doc.createElement('style'),
        elements = [],
        element
      doc.documentElement.firstChild.appendChild(style)
      doc._qsa = []

      style.styleSheet.cssText =
        selectors +
        '{x-qsa:expression(document._qsa && document._qsa.push(this))}'
      window.scrollBy(0, 0)
      style.parentNode.removeChild(style)

      while (doc._qsa.length) {
        element = doc._qsa.shift()
        element.style.removeAttribute('x-qsa')
        elements.push(element)
      }
      doc._qsa = null
      return elements
    }
  }

  return function (options) {
    // factory
    options = options || {} // 短路语法
    var selector = options.selector || '.tagcloud', //默认选择class为tagcloud的元素
      elements = doc.querySelectorAll(selector),
      instance = []
    for (var index = 0, len = elements.length; index < len; index++) {
      options.element = elements[index]
      if (!!TagCloud._set(options.element)) {
        instance.push(new TagCloud(options))
      }
    }
    return instance
  }
})(window, document)
